A Brief Look Into EV Smart Charging And Why It Makes Sense


What is EV smart charging? Why do we need it to move electric car adoption forward?

My wife and I bought our first electric vehicle six years ago this summer. It was a signature ‘Blue Ocean’ 2013 Nissan LEAF, which my sister-in-law affectionately named LEAF Erickson. We have enjoyed freedom from the pump, smooth and exciting driving, and the assurance of a simple drive train (as a mechanical engineer who inspects draw bridge machinery, I’ve grown a healthy distrust of moving parts).

We loved it so much we bought our second LEAF, LEAFam Neeson, in 2015, to go all electric. When I skid LEAFam Neeson into a tree after driving a refugee to work in a blizzard we replaced it with a 2017 Chevrolet Bolt, which we love just as much. Our joy of owning an electric vehicle has spread to my parents, who now own a 2019 Bolt. Electric vehicles continue to improve every year and I can confidently say I will never go back to gas.

Editor’s Note: Alex Waardenburg is very interested in electric vehicles and is currently working on a research paper about EV smart charging for his master’s degree program. He reached out to us with this article, as well as a survey that you can take to help him out with his research.

But, one aspect of driving an electric vehicle hasn’t improved and it really perturbs me. Electric vehicle charging is still so… dumb. EVs are sophisticated computers with massive amounts of energy storage and an internet connection, but their charger is no smarter than a coffee maker from the 1960’s!

Sure, every vehicle manufacturer has a pilot program, a partnership, or done a study of smart charging. Every time I see a new article about it I’m encouraged that it shows they recognize the potential, but they have not given consumers anything to show for it after almost a decade. All the while startups like eMotorWerks have successfully commercialized smart EV charging stations. It hurts me to say Tesla is no better and it has no excuse. It has the vehicles and the software, which it uses for charging its Powerwall. Why doesn’t Tesla give customers the option of charging their vehicle the same way a Powerwall charges?

A full implementation of smart charging would compensate the vehicle owner just by charging when electricity is the cheapest and reducing charge power when electricity is expensive. And, increasingly cheap electricity corresponds to times when renewable energy is abundant.

Accelerating the implementation of electric vehicle smart charging, complete with compensation, will accelerate the transition to electric vehicles by making them more economical and environmentally friendly. It will also accelerate the transition to renewable energy by giving utilities more control over demand to compensate for the lack of control over electricity supply inherent in renewable energy. That synergy will spiral as more renewable energy makes electric vehicles even more enticing and more electric vehicles make more renewable energy possible.

Of course, the true potential of smart charging can only be unlocked by utilities, and they are not going to play ball until EV smart charging reaches a critical mass to make it worth their effort. That will happen inevitably as electric vehicle adoption accelerates, but there are important steps vehicle manufacturers can take now to accelerate the point at which their fleet reaches critical mass. I believe the most important step is to work together.

If only Tesla and GM coordinated, they would double their fleet overnight and reach critical mass together because all of their vehicles are internet connected, and they could both utilize all of their current fleet. That would show manufacturers like Nissan the importance of including internet connectivity to all of their electric vehicles. Of course, they should coordinate with every manufacturer who is willing to reach critical mass even sooner in all markets. It would allow vehicles from small manufacturers (who may never reach critical mass on their own) to be utilized. Since it is all coordinated by software, each manufacturer can leave the conglomeration with their entire fleet overnight with a software update as soon as they reach critical mass on their own.

That is what vehicle manufacturers can do, but I am not a vehicle manufacturer. I also do not think venting on the internet is going to change anything or help anyone. No, my plan is to help manufacturers achieve critical mass another way; through increasing the utility of each electric vehicle.

I am writing a research paper for my master’s degree and I chose to write about a novel way to increase the utility of each electric vehicle for smart charging by allowing electric vehicle owners to select a target charge range instead of a single value. The target range gives algorithms additional flexibility to choose the absolute best times to charge, even from day to day, allowing electric vehicles to be used for medium term energy storage (some days are sunnier than others!). It also gives smart charging algorithms extra flexibility to deal with the unpredictability of energy markets.

In my research paper, I will attempt to quantify how much improvement it would provide. My analysis of using smart charging to increase self-consumption of solar power shows that using a target charge range improves self consumption by 15% over using a target charge value! However, modeling the benefits of other aspects heavily depends on how large users make their target charge range. That is what you can do to help.

I have made a survey to estimate how large EV owners will make their range to make my analysis more accurate. If you have driven an electric vehicle, would you please fill out my survey, so I can make my research even more useful to someone who does manufacture electric vehicles with, say, 310 miles of range and 220 miles of range?

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68 Comments on "A Brief Look Into EV Smart Charging And Why It Makes Sense"

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As more complex a system becomes, as more probable problems will occur and/or the system is easier to hack.
And if I need to charge quickly for not loosing my job or for some sort of emergency, I need to charge quickly. But that will be made expensive. The prices will rise and fall multiple times a day as quickly as fuel prices currently do in some countries so you nearly have no chance to finde the cheapest time to charge for your needs.
And as I already said, it will be easier to hack a whole network of such a system. Terrorists etc. will like it.


Do Not Read Between The Lines

it would be easy to build in the failsafe principle that the car will always be charged when required.
Smart charging is just a system that spreads out charging.

Using electricity whenever you want is what makes electricity expensive. Smart charging is a way of getting cheaper electricity. If you needed electricity immediately, yes it would be more expensive for that electricity, but overall it would lower cost.

It’s no different to want immediate service from hotels, airlines, taxis, or trains. You might occasionally need that, but mostly you have time and you can schedule in advance and save money.

Compared to just about any other form of energy, electricity is CHEAP.

The world has gone mad on EV when realistically its a non starter till the charging time is improved as to fill a car you can be in and out in 10mins,45mins min on EV and that doesn’t include trying to find a free charger. Having to turn heaters off to preserve battery life is a joke then drive like a Sunday driver is a distraction and dangerous as you are more concerned with the percentage going down rather than just driving. The only advantage Tesla has is the range and quality of vehicle which comes at a huge price

If you drive 300+ miles every single day, you’re better off driving a gasser (or move closer to work) since fill up time is about 15 minutes to get to/from gas station. But for the rest of us who drive under 100 miles a day, EV is far quicker than any gasser since charging time is only 10 seconds.

I’ve put 18,000 miles on my EV since buying it a little less than 11 months ago. I’ve only ever used a fast charging method 4 times since buying it and that was only because we took two trips that were further than we could go without doing it. It was totally a non-issue with the longer charge rates since we intentionally planned activities around those stops. Sure, the infrastructure doesn’t exist for this to work if everyone suddenly owned an EV, but we all know that it’s a chicken and egg problem, and the eggs are being hatched.

Do Not Read Between The Lines

Obvious troll is obvious.

I don’t know, man…..you will be surprised how many believe this crap. People thend to fear what they don’t know.

Ignorant troll who has never driven, much less charged, an EV. Early this afternoon, with the sun shining on my solar array, I decided to top off the charge on my Model 3. I walked to the garage, plugged it in to the powerwall, and returned to my living room to relax. It was traumatic.

The charging time is a non issue for 98% of owner. You buy a car that can drive through your day work and get back home where it sits for the night where there’s plenty of time to refill the battery.
If you happen to drive all day long, filling many time, you don’t need an EV, you need a diesel car with a sleeper.
It’s probably less than 2% case, so EV is a real answer to the remaining 98%.
And then the smart charging thing is just the icing that could make EV even more usefull.

I’d love to get a smart charger but given my utility charges $0.08 kWh 24/7 with no options, it just doesn’t pencil out. My eGolf and Pacifica both have built in timers but I haven’t bothered with them yet.

I have same pricing all day long since I’m on pv but i still charge off peak and on peak solar. Come on, it’s not hard and it won’t cost you a thing to help out.

Just a thought – we should help the utilities when they are not being helpful here?

We need more access to electric vehicle charging, NOT smarter charging.

Non-“Smart Charging» is really NOT a huge problem. Solution is simple, adding some software to vehicle to schedule when to charge.

A much larger problem that needs to be addressed is access to charging for residents in apartments and multi family units without dedicated parking/charging facilities. This would bring charging and access to electric vehicles to as much as fifty percent of families not currently able to access.

If you can charge you battery really quickly and the battery is big enough to leave the last 20-30% unused if necessary to avoid damage by fast charging, you don’t need chargers everywhere. No need to put tripping hazards (or far less efficent wireless charging) everywhere which also consumes ressources.


Every car gets parked, we need L2 charging available where cars park. Low power draw over long periods of time.
And then for trips there needs to be fast chargers along those routes, 30min every 200mi is really not that big deal.
Everyone is used to the ICE paradigm, but once they shift to the EV paradigm they will wonder why they didn’t do it sooner. 100% range at the start of every day is very nice. Not having to stop at service stations is also very nice.

As a huge fan of EVs, and someone who wants to see the transition to EVs happen sooner rather than later, I still wouldn’t feel fully comfortable with an ev as my sole vehicle unless I knew I could get 200 bona fide miles of range under 20 minutes. Tesla’s V3 supercharger will hopefully enable that.

Just in case the zombie apocalypse happens, right?

I mean it’s 150 miles in 20 minutes right now in my LR RWD Model 3. If you start out your trip with a full charge you can drive for more than 3 hours on the first leg. Then stop for 20 minutes and drive over 2 more hours. Then you arrive with 40 or so miles still left. Stopping 20 minutes for a 400 mile trip is no different really than in an ICE car.

You may be different but stats show most people decide to fly when a road trip gets over 400 miles. But even then you can continue on stopping every 2 hours for 20 minutes forever.

Do Not Read Between The Lines

Smart charging is a way of allowing the grid to operate more cheaply, efficiently and cleanly.
It’s an entirely separate issue from charging infrastructure.

Not what this article is about. I can already schedule charging – I do that routinely to help the grid operate better. The author is either talking about something else, or simply doesnt know much at all about EVs. I doubt that since the author owns 2 EVs.

Have you explored 2 way chargers? This allows EV’s to feed electricity to grid at high prices and charge vehicle at low price.

Do Not Read Between The Lines

Smart charging provides most of the benefit of V2G.

Smart charging gives some benefit, but if you could suddenly access the batteries of a few hundred or thousand EV in mid-summer you could avoid using an expensive peaker plant. Currently only CHAdeMO works with V2G, not level 2 or CCS, so it’s pointless to think too much about V2G until it’s a universal protocol and the necessary hardware is installed.

I would argue that utilities have a vested interest in that on-board hardware and might think about subsidizing part of that cost pre-sale.

The problem with V2G is unless you build out a nationwide infrastructure of daytime chargers for where the cars are parked during the day, a majority of those hundreds of thousands of EVs will be charging late in the day and at night at home when you don’t need them.

Our rates in the Nashville Metro area are the same 24/7, and our utility has no plans to change that. It’s a moot point for many people, unfortunately.

The best US market for smart charging at the moment is probably PJM in the east and central US, while the largest market for EVs is currently in California. This will change. Many parts of Europe have good rates for smart charging but it is evolving. There are competing standards, but some say none of the established standards for control are fast enough for the frequency regulation market. But smart charging is coming and everyone in the business seems to be getting more aware that it is coming.

What charger do you show in the picture? It did not have a caption and seems like a 2 way charger.

The J1772 EVSE in the first photo (the charger is an electric module included in all EV’s) is a JuiceBox. The J1772 North American charging standard is for one-way current flow only. The AC charging module in each EV would need to be modified to support 2-way current flow while charging. Nissan has demonstrated 2-way current flow when using its CHAdeMO DC fast charging connector that supports 2-way current flow. I don’t know whether the CCS DC fast charging standard used by most EV’s supports 2-way current flow.

The EVSE in the second photo must be a European model because the charging cable isn’t permanently connected to the EVSE as in North America. I do not know which EVSE is pictured.

Smart this, smart that and to be honest not much of what is labelled ‘smart’ is hardly more than one level above dumb.
In the UK, we have this programme called ‘Smart Electric Meters’ most of them are anything but smart.
We don’t have demand pricing here in the UK at the moment but who can tell what mess we will be in come 30th March. We may have a 2GW shortfall on power in France decides to switch off the interconnector.

Do Not Read Between The Lines

Smart metering is entirely separate from smart charging.
Brexit won’t affect electricity at all.

Smart metering is separate now because they didn’t program it to include smart charging yet.
Smart metering can manage smart charging with hour rate and even with dedicaded rate just for the charging part.
It can also trigger the charging session if the utiliy want that.
Smart meter can do what we want them to do. It’s a two way software device that you can extract all data point and charge for whatever profile, so be it smart charging or smart use or not is a matter of utility choice and consumer benefit or not.

Alex: if you’re going to write about smart charging, please give consideration to the interop standards that enable a seamless experience for the customers. ISO 15118.

One thing that would help ISO 15118 would be if ISO allowed free download of the specs like the IETF does with Internet standards rather than requiring payment for each of the eight parts. A lot of Internet protocol innovations would never have occurred and there would be far less robust implementation if the IETF charged for standards. There is an OpenV2G project to provide an open implementation which is a good thing. It would have helped if J1772 wasn’t so dumb, providing no communications other than the square wave duty cycle hint to the EV. Apparently SAE wanted something that could be implemented with nothing more than 1950s or 1960s technology. This results in having to put the control signaling over the power lines rather than have a simple physical interface such as differential pairs on non-power pins (or just use 4 pair TP Ethernet as-is). For Ethernet, the signal pins could have been close together and small as they are on RJ45 connectors. Unfortunately no such thing on J1772. The good news is IEEE 1901 (aka BPL) is becoming inexpensive. This is a bad application for wireless. Can’t fix past mistakes.
I expect utilities pushing for “smart charging” when it is both ways. Right now there is no incentive for the utility to work on smart charging since most cars will be charged mainly at night when the load is low (yes there is a time in the evening when the load is higher but that is from a utility view comparatively minor). When the number of EV’s grow to where the pool of grid connected batteries is noticeable as a power draw, it will also be noticeable as a possible power source, and I would guess at that time utilities will start doing two way smart charging, where the utility would probably deplete your battery to the minimum set level you have to replace peaker plants and then fully recharge your battery at night for a very reasonable rate (possibly free). I think there are utilities looking at this right now, and I would guess you will see some version launched at big scale within 3-5 years. With that said, there will be places where this wont happen even within 10 years. I mean, even though everyone says Tesla Super Chargers are abundant everywhere, there are places in the US… Read more »
Do Not Read Between The Lines

Many utilities won’t be very interested in V2G. They want you to buy electricity through them, not sell it to them. They will want to spend money on batteries at grid level and use those instead.

Utilities also want to spend more money on the last-mile distribution so they can make a profit on the investment, A software system that helps reduce demand problems, will reduced required investment and reduce the utility’s profits.

But that doesn’t matter for smart charging in many cases since it’s single direction, and bypasses the utility to a larger distribution level.

My car charging occurs between midnight and 5 am, mainly – some days longer, depending on SOC. Utilities with peaker plants don’t let those plants cool off at night, so there is a minimum level of generation ocurring anyway. It the grid doesn’t need it, the plant owner has to pay the grid operator to take it. I understand how smart charging could be employed to even this out, and perhaps one day it will be feasible – but with today’s battery tech that sort of thing is not healthy for your car battery. I do not want my car involved with it.

There are a number of aspects of current grid operation that are sub-optimal. Many of them will need to be addressed before smart EV charging can realistically contribute.

“There are places in the US where the closest Tesla Super Charger is more than 2000 miles away”

You must be taking about Alaska. Because a simple look at the Supercharger maps shows that this is very false in the Continental US. You’d have a hard time finding a place more than 200 miles from a Supercharger.

He must mean 200 miles. 2000 is absurd.

UK based MyEnergi has a unique approach. https://insideevs.com/yes-your-ev-can-charge-on-sunshine/
We don’t have to wait on utilities. We just have to focus on where the EV sets idle which is typically at home during the evening hours and in a workplace parking lot by day. The smart EVSE can do the rest.

I just read this article twice, and I must have missed it somewhere, but in twenty words or less, What is “Smart Charging”? Is it a grid thing, is it a vehicle thing, is it a capacity thing, is it a floor wax, or is it a desert topping? Sorry, I don’t get it, can you enlighten me?

I already generate via solar, and time shift my usage to off-peak times with the existing timers in my EV, what else is there?

Using EV batteries to discharge back to the grid during peak demand periods to eliminate the need for peaker plants, usually natural gas powered, that run only during peak demand periods and sell that power at a premium. The peaker plant is also designed differently (fast startup & shutdown capability, better “bottling up” to retain heat when not under demand) than baseload plants, meaning more expensive.

And also charging more when electricity is abundant. Say you have a 250 mile range and a 30 mile commute. You don’t want battery below 100 – comfort level and staying out of the bottom for battery health.

Monday is cloudy. No charge. Tuesday is sunny but not too hot to have much a/c use so your car charges right when you get home since there is excess solar. Wednesday is sunny but hot so no charging. Then it is really cloudy again so Thursday night the can charges to maintain the minimum. Weekend gets a complete fill since factories are closed – but only if the sun is out. If weather is predicting clouds, then it charges overnight.

“increasingly cheap electricity corresponds to times when renewable energy is abundant.”
Where? In SoCal the ev schedule is 11pm to 8am for biz…9¢ per kWh…what renewable is abundant during this time? Not much wind in this area…

Residential customers:
“The lowest rates on the TOU-EV-1 plan are between 9pm and 12pm every day, all year. 13¢ per kWh“

I must say i a bit confused myself as to why CA prefers to give free electricity to neighboring states during peak solar hours rather than drop the rates during these hours.

Give it time. In NC, 1-4 PM in the winter is off peak. Lots of west facing solar panels to handle the afternoon a/c load.

Smartly choosing charge times to adjust demand for utilities is a good idea.

Using EVs as battery storage, to discharge back to the grid, is not. You’re just accelerating the degradation of your car’s most expensive component. In order to make up the cost of the grid tie in hardware, you’ll have to add many charge/discharge cycles, shortening battery life. People will get this once EVs are older and they sell theirs used. Leaf owners who’ve sold already start to get it.

Luckily, Tesla seems to get this, too. Nissan, not so much.

Correct. When battery tech can incorporate this, it will be fine. Until then I won’t hook up my car that way.

We build for 0.1% events – this would not be a daily thing.
My hospital has diesel generators (they all have generators of some type). They are contracted with the utility to fire them up in peak periods. Happens 2-3 days a year for an hour. Ok – so that is a 1% event but still not daily. It makes a lot more sense to throttle back on other things. And our utility does that too. It is a little bit of – “All of the above”.

When we have predictable battery costs/degradation accounting, we can be compensated adequately for using our batteries. When range is 335 and longevity is measured in 300k miles – we can give a little degradation to the utility. Oh wait – we are there.
Longevity is measured in time and charge cycles. If you don’t drive a lot and have a big battery, the utility pulling a bit here and there is not going to make a difference.

You might check out the utility-OEM open vehicle-grid integration platform. It’s multi-input, multi-use case, customer-friendly, and scalable.

Does anyone have good information on when it’s cheapest or most environmentally friendly to charge? A lot of days (nights), I only need to charge for 1 or 2 hours. Curious, when that would be best to schedule. I live in Portland, OR

If your power generator employs peaker plants for high demand periods, the peaker will still be running (and generating) at a lower level during off peak times. The unneeded power is not currently stored in many locations. Therefore charging at night might suit your criteria, even though the power is generated by fossil fuel (natural gas).

I have 100% renewable supply, which is wind in my part of the country. When I schedule charging to start at midnight, those windmills aren’t pumping out the power – but my contract drives the demand for renewables, which plays a significant role in utility forecast and planning.

So the landscape is a bit complex – generally charging during off peak times will be the best way to go, no matter the source or the price. Contributing to demand during peak times unnecessarily doesn’t do any of us any good, and tends to drive demand forecasts unrealistically.

I do. Whenever your rates are the cheapest. That is when the utility prefers you to use electricity. Most cars have start timers in them that you can program to charge when rates are the lowest. Just use them with your low-cost dumb wall box and it will effectively become smart enough..

Absolutely agree with the “dumb wall-box” notion EXCEPT for the case of the Nissan Leaf which makes it ridiculously painful to set the separate start-stop timers every time to charge from any starting %SOC to a desired ending %SOC.

Dumb wall box – YES. Bells and whistles – NO.

In the Tesla case it’s more or less “set & forget & no sweat” via a dead-easy in-car user interface.

That still isn’t perfect. It should have end times but it doesn’t. Even Nissan has an end time.

It does, but you can’t set an end time if you set a start time and vice-versa. So far I haven’t been able to fix that in a Leaf, but the UI is painfull and totally counter intuitive.

Try pacificpower dot net and search on “time of use”. It answers most questions for pacpower customers. PGE may have something similar.

Normal, everyday electrical rates result in my paying approx. 2.5 cents per mile to drive my Tesla. How much money can I save? Quite the ridiculous subject to pontificate on.

Yep. Tires for us Tesla owners cost more than that per mile.

Not for me for 19″ all seasons. $1000 every 40k. 19in Primacy’s. 70D.
70k miles and doing ok on my second set.

$218 each at tire rack. Allows $120 for mount/balance to hit the $1000 mark.

Ok – now imagine a world where fossil fuel use is damaging the equilibrium of the climate. Understand that that fuel use has to go away or decline dramatically. The electricity rate you pay today is based on not accounting for that damage and in fact encouraging fossil fuel use by incentives.
Transitioning off fossil fuels is made easier by charging when the wind blows or the sun shines.
It is also really helpful to not have 100 million cars plug in and start charging between 5 and 7 pm when they get home during the week. It is a little bit like working off hours to avoid traffic.
The goal is not to get your mileage charge down to 1.5 cents a mile – it is to save the planet. Does that sound ridiculous?

Check out w.dcctechnology (Demand charge controller for EV’s)!

Maybe I missed the point here… smart charging seems to exist already. I bought a charger from Emotorwerks for my Leaf back in 2015, but I didn’t really even need it; the Leaf itself included a time-based auto-charging function. I’ve driven an EV now ever since 2015 and 99% of the time I charge during the night when my cost (in the state of Georgia) is only about 1.25 cents/kwh. It’s pretty much free energy for me. On another note, now you can get a reasonably priced 2018 Leaf (still full federal tax credit) that will go 150 miles on a charge, but I admit, the long-distance charging is still not as good for non-Tesla’s. But it’s getting better pretty quickly. So… please help me understand, what exactly is the complaint in this article?

That’s what SMA (PV inverter company) and Audi are working on:
(i’ve bought the Audi etron, and i’ve bought the SMA inverter. The smart charger isn’t available yet…)

Hi Alex,

Don’t get too discouraged by the (educated) skepticism of us readers. You should read our skeptical posts, of course, but don’t immediately accept them as scientific gospel.

Quick story: In 1994, when I graduated from college, I was looking for a job in solar energy. But, every solar energy company that I contacted told me depressing things like, “Why are you wasting your time? The solar industry died in 1982.” and “Solar isn’t going anywhere”. Those companies’ tired skepticism was a result of the brief glory and crashing decline of the early solar hot-water industry during 1976-1982. I’m glad I didn’t listen to the discouraging stories of those early pioneers, because now solar energy is becoming a technological savior, and I got to be a part of that.

Keep up the good fight.

Maybe Tesla does not want to implement such software on its cars because it would decrease even slitly the battery longevity. So maybe a solution could be a warranty based on a volume of kWh instead of a number of km (and/or years). However it would implies more EV educated drivers.

I’ve had a JuiceBox since last summer and have accumulated $16 in smart charging rewards while driving my e-Golf 6,500 miles. It’s not a lot of money but participating in the program hasn’t inconvenienced me in the least and has helped the electrical utility company manage load on the grid. In practical terms all it has meant is charging is delayed when I plug the car in at 7pm, for example, which is perfectly fine with me since I don’t need to drive until the morning anyway.

There is no need for an EV owner to charge his own batteries. This could and should be done offline using rechargeable, replaceable batteries a la Gogoro. You don’t fill up your own propane tank that you use for your bbq grill, do you? You just use it ’til it’s empty, then swap out the empty for a full propane tank that you get at any market.

I charge my PHEV C-Max Energi at home, and I’ve had one for 6 years now. My business partner in our new startup reminded me that in Michigan, over 50% of my electricity comes from dirty coal.

When my current lease runs out, I’m considering buying a low cost EV and a home solar charging station. That way, I’ll be 100% carbon free, and won’t be supporting my regional electric monopoly, Detroit Edison.

I remember when they were called a “utility”, and were regulated by the “Public Service Commission”. Now they are a for-profit company which feels threatened by home solar and car solar charging. They just put forth a rate case proposal to strip solar producers of any time-of-day rates and they are charging a connection tariff for selling them my excess energy production.

Time to cut the wires, and go off grid. Just hoping for battery costs to tumble to half the current cost.